> I can see the argument if you’re familiar with poetry terms,
I think they mean "if you're familiar with Anthropic's family of models". They've had the same opus > sonnet > haiku line of models for a couple of years now. It's assumed that people already know where sonnet 4.6 lands in the scheme of things. Because they've had that in 4.5, and 4.1 before it, and 4 before it, and 3.7 before it, etc.
